Background: To date, there are mainly two diagnostic systems that have been proposed for the diagnosis of Complicated Grief [Horowitz, M.J., Siegel, B., Holen, A., Bonanno, G.A., Milbrath, C., Stinson, C.H., 1997. Diagnostic criteria for complicated grief disorder. American Journal of Psychiatry 154, 904-910; Prigerson, H.G., Shear, M.K., Jacobs, S.C., Reynolds, C.F., Maciejewski, P.K., Davidson, J.R., Rosenheck, R., Pilkonis, P.A., Wortman, C.B., Williams, J.B., Widiger, T.A., Frank, E., Kupfer, D.J., Zisook, S., 1999. Consensus criteria for traumatic grief: a preliminary empirical test. British Journal of Psychiatry 174, 67-73]. There is also no data about prevalence rates of Complicated Grief in a representative sample. The purpose of this study was to compare the diagnostic systems with regard to prevalence, conditional probabilities, and agreement.
Methods: In a sample of elderly persons, features of bereavement, diagnoses of Complicated Grief and related symptoms were assessed. Agreement between the diagnostic systems was determined by kappa statistics.
Results: 18.9% of the sample had experienced a major bereavement, in average 15 years before measurement. The prevalence rates were 4.2% (Horowitz et al.) and 0.9% (Prigerson et al.). The agreement was poor (kappa=.13), i.e. the minority of cases received both diagnoses. The conditional probabilities of developing CG after experiencing a major bereavement were 22.2% (Horowitz et al.) and 4.6% (Prigerson et al.).
Limitations: The findings are constrained to an elderly, urban population. Screening instruments, no clinical interviews, were used to assess psychopathology.
Conclusions: The Horowitz et al. criteria set is more inclusive and less strict than the Prigerson et al. criteria set. The importance of functional impairment and the number of symptoms needed account for this difference. Further research should integrate diagnostic systems in order to achieve international standardization of diagnostic criteria for Complicated Grief.